OHAUS T71P, Service Manual

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CHAPTER 3 MAINTENANCE PROCEDURES
3.2.3 Membrane Switch Replacement
1. Separate the Top and Bottom Housing. (Follow steps 1 – 3 in Section 3.2.1.)
2. On the T71XW, when removing the old Membrane Switch, be sure to extract the
plastic ribbon cable that connects to the PCB’s Keypad Connector.
3. Remove the protective backing from the back of the new Membrane Switch; carefully
position it on the Top Cover, starting at the bottom of the cover. Use a rolling motion
to smooth the Membrane Switch into position.
4. Carefully re-position the Main PCB over its screw holes in the Top Cover.
Re-insert and tighten the screws.
5. Reconnect the cables removed in Steps 4 and 5 of Section 3.2.1.
6. On the T71P, re-insert the hex screws connecting the RS232 Interface port to the
Bottom Housing.
7. Close the Housing and re-insert the four screws.
8. Perform calibration procedures. (See Section 1.8.)
9.
Perform testing procedures. (See Chapter 4.)
Ohaus Corporation www.ohaus.com 3-4 7000 Series T71 Indicators Service Manual